Multiplication Shortcuts
Multiplication of 2 digit with 2 digit
• 67 × 56
• Step 1: 7 × 6 = 42
• Step 2: (6×6) + (5×7) =
71 +4(carry) = 75
• Step 3: 6 × 5 = 30 +
7(carry) = 37
Multiplication of 3 digit with 3 digit
• 789 × 123
• Step 1: 3 × 9 = 27
• Step 2: (8×3) + (9×2) = 42
+ 2(Carry) = 44
• Step 3: (7 × 3) + (1 × 9) +
(8 × 2) = 46 + 4(Carry) =
50
• Step 4: (7 × 2) + (8 × 1) =
22 + 5(Carry) = 27
• Step 5: 7 × 1 = 7 +
2(Carry) =9
Divisibility by 7
Find % ending in 0 or 5
To find the % of any Number
Convert Fractions into %
Multiply the Big Numbers
Squaring a number ending in 5
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352 =?
The successor of 3 is 4
Multiply 3 and 4
Put the answer 12.
Suffix 25.
The answer is 1225.
Squaring the number beginning in 5
• 562 = ?
• Always Add 25 with the
number in units digit
25+6 = 31
• Suffix the square of the
unit digit = 36
Squaring a number beginning in 1

1
18 6
196

142 = ?
42 = 16
Put 6. Carry one
14 + 4 = 18
Add 18 and carry and put the answer in front
Multiplication by 9
• For 1 to 9
• Subtract 1.
• Annex the 9’s complement.

7 x 9 = 63

• For 11 to 19
• Subtract 2.
• Annex the 9’s complement.

17 x 9 = 153

• For 21 to 29
• Subtract 3.
• Annex the 9’s complement.

26 x 9 = 234
Numbers ending in 6
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662 =_________.
a) Write down 6.
b) 2 x (6 + 1) + 1 = 15. Write 5, carry *1.
c) 6 x (6 + 1) = 42 + *1 = 43. Write 43.
d) The answer is 4356.
862 =_________.
a) Write down 6.
b) 2 x (8 + 1) + 1 = 19. Write 9, carry *1.
c) 8 x (8 + 1) = 72 + *1 = 73. Write 73.
d) The answer is 7396.
Multiplication by 12
• Let’s understand this method by
taking an example.
• 345 × 12
• Step 1:
•
Write 345 as 0345.
• Step 2:
• Multiply each and every digit with
2 and add it to its right neighbour.
This process is started from right.
Multiply 5 with 2 and add it to its
right neighbour. 5 has no right
neighbour so add the
multiplication to 0. This gives 10
as a result. So 0 is written down
and 1 is carried forward.
• Step 3:
• Multiply 4 with 2 and add it to 5.
Carry 1 is added to the result. This
gives 14 as a result.
• 4 is written down and 1 is carry
forwarded.
• Step 4:
• Multiply 3 with 2 and add it
to 4. Carry 1 is added to the
result. This gives 11 as a
result.
• 1 is written down and 1 is
carry forwarded.
• Step 5:
• Multiply 0 with 2 and add it
to 3. Carry 1 is added to the
result. This gives 4 as a
result.
MULTIPLICATION BY SIX
Practice what is half of ?

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6
5
4
8
7
2

To each number add ‘half’ of the neighbour;
‘plus 5’ if it is odd

1
• 3 0 6 2 2 0 8 4x6
• 2 3 7 3 2 5 0 4
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2
4
3
1

1
0 4 4 3 0 5 2x6
2 6 5 8 3 1 2

Multiplication shortcuts- DOWNLOAD ENABLED

  • 1.
  • 2.
    Multiplication of 2digit with 2 digit • 67 × 56 • Step 1: 7 × 6 = 42 • Step 2: (6×6) + (5×7) = 71 +4(carry) = 75 • Step 3: 6 × 5 = 30 + 7(carry) = 37
  • 3.
    Multiplication of 3digit with 3 digit • 789 × 123 • Step 1: 3 × 9 = 27 • Step 2: (8×3) + (9×2) = 42 + 2(Carry) = 44 • Step 3: (7 × 3) + (1 × 9) + (8 × 2) = 46 + 4(Carry) = 50 • Step 4: (7 × 2) + (8 × 1) = 22 + 5(Carry) = 27 • Step 5: 7 × 1 = 7 + 2(Carry) =9
  • 4.
  • 5.
    Find % endingin 0 or 5
  • 6.
    To find the% of any Number
  • 7.
  • 8.
  • 9.
    Squaring a numberending in 5 • • • • • • 352 =? The successor of 3 is 4 Multiply 3 and 4 Put the answer 12. Suffix 25. The answer is 1225.
  • 10.
    Squaring the numberbeginning in 5 • 562 = ? • Always Add 25 with the number in units digit 25+6 = 31 • Suffix the square of the unit digit = 36
  • 11.
    Squaring a numberbeginning in 1 1 18 6 196 142 = ? 42 = 16 Put 6. Carry one 14 + 4 = 18 Add 18 and carry and put the answer in front
  • 13.
    Multiplication by 9 •For 1 to 9 • Subtract 1. • Annex the 9’s complement. 7 x 9 = 63 • For 11 to 19 • Subtract 2. • Annex the 9’s complement. 17 x 9 = 153 • For 21 to 29 • Subtract 3. • Annex the 9’s complement. 26 x 9 = 234
  • 14.
    Numbers ending in6 • • • • • • • • • • 662 =_________. a) Write down 6. b) 2 x (6 + 1) + 1 = 15. Write 5, carry *1. c) 6 x (6 + 1) = 42 + *1 = 43. Write 43. d) The answer is 4356. 862 =_________. a) Write down 6. b) 2 x (8 + 1) + 1 = 19. Write 9, carry *1. c) 8 x (8 + 1) = 72 + *1 = 73. Write 73. d) The answer is 7396.
  • 15.
    Multiplication by 12 •Let’s understand this method by taking an example. • 345 × 12 • Step 1: • Write 345 as 0345. • Step 2: • Multiply each and every digit with 2 and add it to its right neighbour. This process is started from right. Multiply 5 with 2 and add it to its right neighbour. 5 has no right neighbour so add the multiplication to 0. This gives 10 as a result. So 0 is written down and 1 is carried forward.
  • 16.
    • Step 3: •Multiply 4 with 2 and add it to 5. Carry 1 is added to the result. This gives 14 as a result. • 4 is written down and 1 is carry forwarded.
  • 17.
    • Step 4: •Multiply 3 with 2 and add it to 4. Carry 1 is added to the result. This gives 11 as a result. • 1 is written down and 1 is carry forwarded.
  • 18.
    • Step 5: •Multiply 0 with 2 and add it to 3. Carry 1 is added to the result. This gives 4 as a result.
  • 19.
    MULTIPLICATION BY SIX Practicewhat is half of ? • • • • • • 6 5 4 8 7 2 To each number add ‘half’ of the neighbour; ‘plus 5’ if it is odd 1 • 3 0 6 2 2 0 8 4x6 • 2 3 7 3 2 5 0 4 • • • • 2 4 3 1 1 0 4 4 3 0 5 2x6 2 6 5 8 3 1 2